Structural and functional characterization of the IpaD π-helix reveals critical roles in DOC interaction, T3SS apparatus maturation, and Shigella virulence.

ABSTRACT: Shigella spp. are highly pathogenic members of the Enterobacteriaceae family, causing ∼269 million cases of bacillary dysentery and >200,000 deaths each year. Like many Gram-negative pathogens, Shigella rely on their type three secretion system (T3SS) to inject effector proteins into eukaryotic host cells, driving both cellular invasion and evasion of host immune responses. Exposure to the bile salt deoxycholate (DOC) significantly enhances Shigella virulence and is proposed to serve as a critical environmental signal present in the small intestine that prepares Shigella's T3SS for efficient infection of the colonic epithelium. Here, we uncover critical mechanistic details of the Shigella-specific DOC signaling process by describing the role of a π-helix secondary structure element within

SUBMITTER: Barker SA 

PROVIDER: S-EPMC11400957 | biostudies-literature | 2024 Sep

REPOSITORIES: biostudies-literature